I think I put it in my other thread, but how i’ve seen reaserch done on a similar game (Capitalism 2 for those that care), research could be direceted at different areas, but features to research not selected. They were unlocked automatically at different levels of research.
This meant that you could have 4 reaseach centres, one working on the widgets, another on the grommets, one on the knobs and one on the product itself. Increased reasearch level in each would increase its quality, and the quality of the product was based on it’s own quality, plus a contribution from the qualities of the components being used to make it. If you bought in components you had less control over quality level. I think it also had a level for raw material quality that went into making components to give 3 tiers of quality contribution.
Poor quality in any one area would let down the whole product (cars with crap engines for example).
This would take away the already quite complicated research path for different features, and give more longevity to research centres as even after you’ve finished researching all features available, you can still keep researching to make your cars better overall quality.
You could have reaserch paths for:
Production methods (unlocks more production stations and allows some features to be added into the line)
Chassis (unlocks different body styles, materials, sports bodywork etc)
Suspension (suspension, brakes, wheels)
Powerplant (engine types, forced induction, hybrid, EV)
Drivetrain (manual, automatic, FWD, RWD, 4WD)
Interior (seats, trim level, toys & gadget, infotainment)
You could have the area selectable, and that would research at a slow rate in each sub-area, and as the game moves on, you could build more R&D capacity and select the sub-areas individually to reasearch faster.